When I turn off my bedroom light at night, the room is still lit up like the bridge of the Starship Enterprise. No, I'm not some sci-fi fanboy, just a gadget-happy materialist.
In one corner, I've got a desk with a PC on it. Six button lights on my two monitors glow orange. The PC power button blinks bright green. The speakers have a red light near the switch. My desktop microphone has a shockingly bright green light that casts a circle on the ceiling, as if I'm calling Batman. It's all plugged into a generic surge protector, which has a very bright red light on the toggle switch.
My wife usually leaves her work laptop, a MacBook Pro, and her personal laptop, a Dell Studio, charging in the bedroom. The Mac throbs with a blue-green light that gradually brightens, then dims, then brightens again like an airport beacon. Her Dell shines a small, dim light in the front. And the AC adapter has a light ring around the plug.
We also have a TV in the bedroom, and it has a cable DVR plugged into it. The DVR has a bright red light that's pointed straight at the bed. The TV and the DVR each has a smattering of other lights.
We've got two more surge protectors, each with a bright red light. Our e-books have lights that remain on when charging.
Our bedroom has a door to a bathroom, in which our electric toothbrushes flash amazingly bright green lights. Even when we close the door, you can see the seam around and under the door flash green! green! green!
Even with the room lights off, it's almost bright enough to read by the collective light produced by all of those status lights. And half of them are flashing. I'm supposed to sleep? Isn't this how they torture inmates at Guantanamo?
I wrote a column in this space four years ago about how incredibly annoying all these gadget status lights are and demanded that device makers get rid of them.
I didn't expect manufacturers to respond. And in fact, the problem is getting worse. The number of gadgets we use keeps growing, and each device seems to have more and brighter lights.
Since I wrote that column, new research has emerged that reveals how incredibly bad all of those lights can be for our health.
Lights on during sleep harms health
New science has shed light on various health effects of sleeping in a room that isn't dark.
Lights at night can make you depressed and fat. An Ohio State University experiment on mice led researchers to conclude that even dim light in a room during sleep may cause depression. In a different study, Ohio State researchers found that sleeping in a dimly lighted room increases the amount of hunger experienced during the day, which can contribute to weight gain and possibly susceptibility to diabetes.
Sleeping in a room with dim lights increases a woman's chance of getting breast cancer, according to research conducted at the National Cancer Institute and National Institute of Environmental Health Sciences. The reason is that the body produces a cancer-fighting hormone called melatonin at night during sleep. But this process is interrupted if the room isn't dark.
Another study conducted at the Scheie Eye Institute at the University of Pennsylvania School of Medicine found that babies who sleep with a night light have an increased risk for developing short-sightedness, or myopia. Just 10% of babies who slept in the dark most nights needed glasses, compared with 34% who slept with night lights and 55% who slept with room lights on.
The bottom line is that the human body is designed to sleep in total darkness. All those gadget lights are lighting up our bedrooms at night and damaging our health.
LED lights are toxic
The little lights that are built into our phones, computers and other gear are made with a semiconductor technology called the light-emitting diode (LED). These lights are advertised as "eco-friendly." But a recent study by University of California at Irvine's Department of Population Health & Disease Prevention found that LED lights can contain hazardous substances, including lead, arsenic, nickel and more than a dozen other deadly materials.
According to a release by the university, "lead, arsenic and many additional metals discovered in the bulbs or their related parts have been linked in hundreds of studies to different cancers, neurological damage, kidney disease, hypertension, skin rashes and other illnesses."
In general, say researchers, the brighter the light, the more poisons they're likely to contain. Colored lights contain more lead than white ones. Red lights were found to contain up to eight times the amount of lead allowed by California law and about 35 times the amount allowed by federal law. That's right: Red LED lights are so toxic they're illegal.
Researchers say LED lights are generally safe unless they break, in which case they advise that you construct your own hazmat suit to deal with the toxic cocktail that spills out.
One major ongoing risk is car accidents. When cars collide, the LED lights built into the dash, as well as gadgets and computers in the car, can shatter, causing a release of toxic substances that experts say should be treated like any other hazardous materials spill. If LED traffic lights are damaged, it's especially bad because those LEDs are so bright and numerous. Unfortunately, the risk is typically ignored, and emergency crews are routinely exposed to these hazardous materials without protection.
There's also an environmental cost. Current law ignores the risks of LED lights, which are legally disposed of in landfills. The toxic metals in the lights, especially copper, can make its way from landfills into lakes and rivers, poisoning wildlife.
And when gadgets are discarded and "recycled," they're often handled by children in filthy Chinese processing centers who have to contend not only with the toxic materials required to make computer equipment function, but also the materials in the lights, which aren't even necessary.
What can you do?
A single LED light on a single gadget is no big deal. But most people surround themselves with dozens of devices -- all with their own lights -- in their bedrooms, homes, offices and cars. These lights are incredibly annoying, damage our health and represent a toxic hazard both for people and the environment.
Worst of all: They're unnecessary! Sure, a status light may alert you to an incoming e-mail, or tell you at a glance that something is receiving electricity. But we now know that benefits like those are vastly outweighed by the costs.
You can protect yourself to some degree by keeping as many devices as possible out of your bedroom. Put black electrical tape over the lights on those items you do keep in the bedroom.
And treat any broken LED lights with extreme caution.
Now that we know how toxic and dangerous LED lights can be, gadget makers have a responsibility to eliminate all lights that aren't absolutely necessary. They waste electricity, annoy users, wreck health and pollute the environment.
Gadget makers love lights. But getting rid of them would be the brightest thing they could do.
Mike Elgan writes about technology and tech culture. You can contact Mike and learn more about him at Elgan.com.
This story, "Why Gadget Lights Are Dangerous" was originally published by Computerworld.